I'm having a problem adding a 320X240 and 320X256 screenmodes with the screenmode preference program,they will not appear in my list of available screenmodes to choose from.

If I checkmark the doublescan option then they will appear in my list of available screenmodes to choose from, low resolution programs will automaticallyuse them but my monitor can't handel them. out of range.

My monitor is capable of using 320X200, 320X240 and even 320X256, as tested on a PC and not using the graphics card to upscale the image before sending it.

Can anyone tell me what the doublescan option actually does and how to add these low resolution screenmodes to my list of available screenmodes without it ?